The present invention relates to a stretcher or hospital bed. More particularly, the present invention relates to a stretcher which facilitates taking x-rays of a patient located on a support surface of the stretcher.
Although the term xe2x80x9cstretcherxe2x80x9d is used throughout the specification of the present application, it is understood that the novel features of the invention may be incorporated into any type of bed or patient support device.
Stretchers or beds which include structures for holding an x-ray cassette are known. See, for example, U.S. Pat. Nos. 1,768,769; 3,774,045; 4,193,148; 4,584,989; 4,651,364; 4,893,323; 4,905,266; 4,916,725; 4,926,457; 4,947,418; 5,155,758; 5,255,303; and 5,422,928.
During an emergency or trauma situation, it is important to have the maximum flexibility in placement of an x-ray cassette relative to a patient. In addition, it is important to provide the best x-ray image possible on the x-ray cassette. Typically, x-ray radiation spreads out or magnifies as the distance increases between the patient and the x-ray cassette. Therefore, it is desirable to place the x-ray cassette as close to the patient as possible.
The present invention is related to U.S. Pat. No. 5,996,149, which is incorporated herein by reference. The present invention provides an improved x-ray tray located adjacent a patient support surface of the stretcher. The improved x-ray tray permits the x-ray cassette to be loaded at substantially any horizontal location below the patient support deck by sliding the cassette onto the tray using the hands. Enough room is provided between the frame and the patient support deck for hands to pass between. After the x-ray cassette is loaded on the x-ray tray at a desired horizontal location below the patient, the x-ray tray can then be lifted upwardly by a lifting apparatus to position the x-ray cassette adjacent a bottom surface of the patient support deck to improve x-ray imaging on the cassette.
In accordance with the present invention, a patient support apparatus includes a frame, a patient support deck coupled to the frame, a tray positioned below the patient support deck for supporting an x-ray cassette, and a lifting apparatus for lifting the tray toward the patient support deck. The lifting apparatus includes a shiftable member supported for longitudinal translation relative to the frame. A pair of links are coupled to the shiftable member. A first link of the pair of links has a first end pivotally coupled to the tray and a second end pivotally coupled to the shiftable member. A second link of the pair of links has a first end pivotally coupled to the frame and a second end pivotally coupled to the shiftable member. The shiftable member is movable in a longitudinal direction to spread apart the links and lift the tray. A handle may preferably be provided for moving the shiftable member.
According to another feature of the present invention, the x-ray tray moves only vertically relative to the frame between a lower first position spaced apart from the deck to permit loading of an x-ray cassette on the x-ray tray and an elevated second position located closer to the deck. In accordance with a further feature of the present invention, the x-ray tray includes flanges at opposite ends which are configured to engage cross members coupled to the frame to hold the x-ray tray in the same horizontal position relative to the frame during movement of the x-ray tray.
According to another feature of the present invention, the x-ray tray extends below substantially the entire length dimension of the deck. In accordance with a still another feature of the present invention, the x-ray tray includes a non-slip top surface for engaging the x-ray cassette. According to a further feature of the present invention, the handle is movable to a storage position located under the frame, and the handle is spring-biased toward its storage position.
In accordance with still another feature of the present invention, the handle is pivotably coupled to the frame, and the lifting apparatus includes a spring having a first end coupled to the handle and a second end coupled to the shiftable member to lift the x-ray tray upwardly to its elevated second position when the handle is rotated relative to the frame from a first storage position to a second x-ray position.
According to a further feature of the present invention, the lifting apparatus includes a shaft coupled to the handle and an arm having a first end coupled to the shaft and a second end coupled to the first end of the spring. In accordance with a still further feature of the present invention, the arm is configured such that rotation of the handle to the second x-ray position moves the arm over center to cause the spring to bias the x-ray tray toward its elevated second position. According to another feature of the present invention, the spring is configured to hold the x-ray tray in its elevated second position to urge the x-ray cassette against a bottom surface of the deck regardless of the thickness of an x-ray cassette supported on the x-ray tray.
Additional features and advantages of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of the preferred embodiment exemplifying the best mode of carrying out the invention as presently perceived.